Hoist for vehicle dump bodies



May 5, 1925.

M. s. MARTIN Holsm FOR vEH1cLE-DUMP BODIES original Filed Apr1112.,1921 2 sheets-sheet. 1

Aff.- @u

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May 5, 1925. 4 M. S. MARTIN lHolsT FOR VEHICLE DUMP BODIES original Filed April 1,2. 1921` 2 sheets-sheet .2V

:T the lifting operation.

'Patented May 5,-1925-- i f UNITED STATES MELvIN sWAEToUT n 1,536,959 vPaxrlzNlf OFFICE.

MARTIN, or MINNEAPOLIS, MINNESOTA, assIGNoE'To lGEANT WALDEEI, or sT.IAUL, MINNESOTA.

HoIsT ron VEHICLE DUMPl BODIES.

Application led April 12, 19x21, Serial No. 460,759. Renewed February 2, i925.

To all wiz-om, t may concerti:

Be it known t-hat I, MELVIN SwAn'roUT` MARTIN, a citizen o f the Unite-d States, residing at. Minneapolis, in the county of Hennepin and State of Minnesota, have 'invented new and useful Improvements in Hoists for Vehicle -DumpBodies7 of which the following is a` specification.

MyV invention relates to means for tilting the dump bodies of ordinary dump vehiles and in which the body is tilt-ed to a predetermined angle to facilitate unloading and d-istributing coil, gravel, sand or any other material carried by the body. The means employed constituting my improve? ment includes in its mechanism alever which is interposed between the frame of the vehicle and the body, said lever being swung upwardly to tilt the body by any suitable ram, Winch or elevating' element, that employed not solely constituting my invention but cooperating therewith in a. mannersuitable to apply a lifting effort either automatically or partly by hand. Wit-lrthe presen-t improvement the lifting effort is applied by la powerful Wedging action thereby .minimizing the power required during the initial raising ofthe load and thereafter. This improvement further provides in its mechanism when a. hydraulic ram is employed as the prime power element a lifting or tilting arm against which the wedging elementfunctions so shaped as to yequalize liquid lpressure at all points of In4 dump vehicles of ordinary construction which are at present. in common use as the body or receptacle is tilted, its center if gravity is grad-v ually being brought nearer to a vertical plane passing through the p-intle which connects the receptacle with the vehicle frame,

ofthe tilting mechanism as desired and to thus ordinarily the 'force necessary to tilt the parts and the compression. of the raising Huid ,1s continuously decreaslng, where.-

as with .my improvement this force remains Vsubstantially constant whieh'is an advantage.

A further object of my invention is to provide compensation of theparts that vwill eliminatev body and hoist strains when the load is greater on one side than on the other. and particularly when the hoist is lifting. A further object is to limit lthe travel provide rea. tion.

A further object is to? imite the parts of y adjustment of such limitathe tilting mechanism into a single unit of permitthe escape of liquid-; immediately.

when desired and when the body rea/ches the -desired angle of inclinationlindumping posit-ion.

lith these and other objects in view, my invention comp-rises the features of construction and 'combination of parts hereirr' after described and claimed.

In the accompanying drawings forming part of this-specificatiim, Figure l is a. side elevation of a portion of-a vehicle frame having a. portion ot a dump receptacle pivoted thereto which is designed to 'be tilted by my improved mechanism, said mecha nijsm and receptacle being shown in operating position in dotted lines and a portion of the mechanism being broken away and in section to show more clearly the by-pass in the cylinder WallI of the ram; Fig. 2 is a. plan of the structure shown in Fig. 1, the body or receptacle being removed and a portion of the levers broken away, and

Fig. 3 is a section of a det-ail taken on the line 3-3 of Fig. 1.

In' this specification of which the drawings form a 4part only so much of a vehicle trame or chassis and dump body or receptacle are illustrated as is require/dto show the application of my improved mechanism thereto, the general constructionof dump vehicles being familiar to those skilled in this art.. In the' drawings, A designates the side bars of an ordinary vehicle chassis land B indicates a portion of the dump body or `receptacle which is mounted upon theusual body supporting frame having side bars 10. The body B is hinged near its rear end by means of hinge plates 1l on the chassis, hinge fittings 12 on the body frame and a pintle shaft 13 passing through said plates andfittings.

My improved hoist is ofunitary. type,

that 'is it is so constructed that it can be bodily applied to any ordinary chassis under `the body and its lifting member applied to the body to function in its prescribed manner, that is to tilt the body round about its pintle. This improved hoist has among its component parts a ram which as illustrated is of hydraulic type but it should be understood that a ram of any desired form may be employed such as of a mechanical, electrical or any other type. rlhe ram shown has a hydraulic cylinder 14 disposed longitudinally of the chassis and provided with end caps 15 and 16 threaded thereon. Inside the cylinder is the usual piston 17 from which extendsl the thrust shaft 18, said shaft being adapted to slide through the gland 19 in the cap 15. The cylinder is mounted upon a frame of any suitable construction, that shown having two transverse angle bars 20 and 21 Vwhich are secured by bolts 22 or other suitable means to the side bars A of the chassis. The cylinder cap 16 is formed with. a anged base 23 which is secured upon the transverse angle bar 21 by bolts 24 or other suitable means passing through slots 25 in said base and which are disposed longitu` dinally of the chassis. Thus the cylinder can be fastened in selected longitudinal position on the chassis as' desired. The forward end of the cylinder is slidably sup` ported inthe collar 26 which is formed with laterally extendingY wings or bosses 27 which are bolted or otherwise secured to bosses 28, said last mentioned bosses being formed on the sides of brackets 29 which in turn are bolted or otherwise secured to the angle bar 20. The brackets in addition to rigidly supporting the collar 26, receive and hold rigidly the ends of the channel track bars 'C and D, the opposite ends of said track bars not so held by the brackets 29'being rigidly secured to the angle member 21. The track bars are disposed onthe opposite sides of the cylinder of the ram in parallelism and their upper track surfaces slant upwardly and rearwardly of the chassis in the v'same direction as is assumed by the cylinder. Each channel track member C and D has a pair of sides 30 and 31 spaced apart.

ing upwardly through the channel in trackl or guide rail D. The lower ends of lifting lifting arms slant upwardly and forwardly of the chassis when in lowered position and their upper ends above the track or guide rails are secured to the side bars 10 of the body by links 34, the mode of attachment of the links to the bars and arms being by means of pivot connections 35. The upper ends 36 of the lifting arms are struck downwardly at an angle to accommodate the linkage and the linkage is employed to provide' a freely movable connection between the lifting arms and the body frame.

Arranged above the pair of track or guide rails C and D is a pair of pull rods G and H, Said rods being disposed longitudinally of the chassis and each rod being formed with a longitudinal channel 37 which registers over the corresponding channel in the track or guide rail immediately below. The forward end of each pull rod has a wedging element I, which is formed by a pair of antifriction rollers 38 and 39 bearing upon the upper surfaces of the sides of the track rails and disposed to roll longitudinally along said rails and an intermediate antifriction-roller 40 which is disposed to roll along the under side of the companion lifting arm E or F. All of said antifriction rollers are freely journaled on a' shaft 41 which isfitted into yoke frames 42 on the end of the lifting arm. Thus as the pull bars are pulled backwardly of the chassis a wedging action is imparted between the track rails and the lifting arms, causing the lifting arms to tilt upwardly and raise the vehicle body into the broken line position indicated in Fig. 1 of the drawings. The pulling movement described is imparted to the pull rods by means of the cross arm J which has its body portion intermediate of its ends pivotally attached at 43 to the outer end of the thrust shaft 18 of the ram. The outer extremities of this cross arm are freely connected'to the rearward ends of the pull rods by means o f the pin and slot connections 44 and 45, said connections together with the pivot attachment 43 providing compensation that will eliminate body strain when the-load is greater on one side than the other.

The lifting movement of the arms E and F is defined and limited'by means of stop screws 46 and 47 in the brackets 29, against which the lifting arms may strike. These screws may be adjusted and locked in adjusted' position when desired When so adjusted the upper limit of travel of thev body is limited.

The cylinder is provided in its wall with a bi-passage 48 which is so arranged that when the piston reaches the end of its desired outer stroke the compression luidis releasedand allowed to escape thus ceasing to force the piston beyond its desired movement. To regulate the kposition of this bi-passage and of the consequent outward stroke of the piston the cylinder can be adjusted longitudinally by means of the pair of tie rods 49 and 50 which are disposed -on the opposite sides of the cylinder. The

tie rods are threaded into bosses 51 on theJ cylinder cap 16 and locked in regulated position by means of the lock nuts 52. These tie rods are also secured in regulated position in the angle bar 20 by mea-ns of the lock nuts 53. [When regulatingthe cylinder as described the bolts 24 are first loosened and the slots 25 permit the regulating movement to transpire and after the cylinder has been regulated the bolts are again tightened. The tie rods 49 and 50 also create-an equal. strain on bothfront and rear bars 2O and y 2l and also assist `in -transmitting equal strain upon the hinge plates l1 through the diagonal tension rods and 56. Allof these rods serve to prevent any possibility of the hoisting mechani'smslipping on the chassis and reduce body, hoist and chassis strains. This is a particular advantage in the event of uneven loading of the body.'

The rods55 and` 56 are bolted to the hinge plates l1 and to the angle bar 20.

The lower surfaces. of the lifting arms with which the wedging rollers contact and force the bodyv up into tilting position are` so shaped as tocause the pressure of the liquid 1n the cylinder of the ram to be equa]-v ized at all periods ofthe lifting operation. The shape shown provides a slanting portion 57 during the period `of the stroke when lthe. lifting arm first lifts the body,A

said portion. gradually turning upwardly and merging into the portion 58 when the body finally approaches fully tilted or dumpingvposition. Thls shape 'or a shape approaching it will causel the pressure of the liquid in the cylinder urging the piston outwardly to equalize at the various periods of the lifting operation.

s In accordance with the patent statutes I have described the principles of operation of my invention together with the apparatus which Inow consider to represent the best embodiment thereof but Idesire to have it understood that the construction shown is only illustrative and that the invention can be carried out by' other means and-applied to uses other than those above set forth within the scope of the following claims.

I claim: i 1

1.1In combination with va vehicle chassis having lhinge elements near its opposite sides, a body mounted upon said hinge-elements to tilt upwardly, a ram havingits piston movably connected with lt-he body to tilt the body. upwardly, and having the outl ermost end of its cylinder movably mounted upon said chassis to turn, and ,tie rods coupled to the innermost end of the cylinder 'and to said hinge elements adapted to suppo tra portion of the efr-.rt of the cylinder and relieve strain upon the chasss duing the upward tilting movement of the bo y.

2. In combination with 'a vehicle chassis, .a body hinged to swing upwardly upon said chassis, a pair of cross bars upon said chassis and a ram havinggits piston movably con-- nected with the body to tilt the bodyupwardly and havin'g its cylinderI movably supported at its inner end upon one of said cross bars and secured by tie rods to the other of said cross bars, whereby part of the eflfort of the cylinder during the lifting movement of the ram is transmitted directly from one of the\cro`ss bars to the other to distribute `the lifting eii'ort of the ram more evenly'over. the chassis.

3. In combination .with a vehicle chassis,

chassis to tilt upwardly, a hoist associated *i with said body, to tilt the latter upwardly, said hoist havng a cylinder provided with a. bi-pass in its wall and a piston reciprocable in the cylinder and adapted to uncover said bi-pass at the end of its-stroke and the length Iof said stroke governed thereby, one of said hoist parts being mounted upon 'said chassis and the other connected with said body and said points of mounting and connection .being variable so that the length of stroke of 4 said piston will be governed according to said regulated position of said bi-pass.

` 5. Hoisting apparatus for vehicle bodies, comprising, in combination, a chasss, avvehicle body hinged to said chassis and adapted to swing upwardly into dumping position, a hoist having a hydraul'c cylinder provided with a bi-pass in' its wallv and a piston reciprocable in the cylinder and connected with the body to tilt the latter'by its thrust movement, said piston beingadapted touncover saidfbi-pass at the end of its .outward stroke, a frame securedl tothe chais and l yupon which the hoist cylinder is movably mounted, and adjusting means for securing said cylinder on said frame and' whereby thev position at which the piston uncovers the bi-pass is regulated. y l 6. In combination with a vehicle chassis, a dump body movably'mounted upon said chassis to tilt upwardly, a hoist associated with said body to tilt the latter upwardly, said hoist having a cylinder provided with a loi-pass in its wall and a piston reciprocable in the cylinder and adapted to` uncover said bi-pass at the end of its stroke and the length of said stroke governed thereby, one of said hoist parts being mounted upon said chassis and means for regulating the posiytion of said bi-pass so that the length of stroke of said piston will be governed accordingly.

7 In combination with a vehicle having a chassis, a body carried by the vehicle in l hinged relation to said chassis, a lifting arm below the body hinged near one end to the chassis and movably coupled near its other end to the body whereby an upward swing-- ing movement of the lifting arm on the chassis is adapted to transmit an upward swinging movement to the body, a track disposed in substantially an inclined plane longitudinally of the lifting arm towards the-hinged end of the body, a wedge element movable along the track and below the median portion of the lifting arm adapted to swing the lifting arm upwardly on its connection and a hydraulic ram arranged so that its thrust element will move the Wedge element along said track and beneath said arm, and said arm having a portion of its lower surface with which said wedge contacts against sloping downwardly from both ends so that the pressure of liquid in the ram remains substantially constant at varous periods of the lifting operation.

8. In combination with a vehicle having a chassis, a body carried by the vehicle in hinged relation to said chassis, a lifting arm below the body hinged near one end to the chass's and movably coupled near its other end to.- the body whereby an upward swinging movement of the lifting arm on the chassis is adapted to transm't an upward swinging lnoven'ient, to the body, a track disposed in substantially an inclined plane longitudinaly of the lifting arm towards the hinged end of the body, a wedge element movably disposed along the track and below the median portion of the lifting arm adapted. to swing the lifting arm upwardly on its connection and a hydraulic rain arranged -so that its thrust element will move the wedge element along said track beneath said arm having its surface against whlch said wedge presses so shaped as toequallzeliquid pressure in the ram at various periods lof the the parts and of the strains incident thereto is produced..

10,'In combination with a vehicle having a chassis, a body carried by the vehicle in hinged relation thereto, a guide bar disposed longitudinally of the chassis and resembling a channel iron, a pull rod also disposed longitudinally of the chassis and resembling a channel iron, saidchannel irons being set on edge one above the other, rollers on one end of'said pull rod, part of which rest upon and are guided by said guide bar, a ram having a thrust element coupled to said rod to reciprocate the latter, and a lifting arm passing freely upwardly through said pull rod and guide bar and having its lowerend hinged to the chassis andv its upper end coupled to the body and resting between I' its ends upon part of said rollers, whereby the pull rod and part of said rollers act as a wedge to tilt the lifting arm upwardly when the lifting arm issubjected to the pulling action of the pull rod.

11. In combination with a vehicle chassis7 adump body hinged upon said chassis to swing upwardly, a lifting bar movably associated with said body and chasss for swinging said body upwardly, a ram upon said chassis having a piston adapted to exert a lifting force against said lever bar, and au adjustable stop against which said lever bar is adapted to strike in its swinging movement to regulate the angularity assumed by the body independently of the act-ion of the piston. v

12. In combination with a chassis, a dump body hinged upon said chassis' to swing upwardly, a lifting bar movably associated with said chassis and linked to said body for swinging said body upwardly, aram upon said chassis having a piston rod, a wedging element coupled to 4said piston rod adapted to exert a lift-ing force against the lifting bar, and a stop against which the lifting bar is adapted to strike in the upward swinging movement ofthe lifting bar to limit the swinging movement of the parts independently of the ram.

13. In combination with a vehicle having a chassis, a body carried by the vehicle in hinged relation thereto, a lifting arm hinged to the chassis at its 'lower end and having its upper end struck downwardly and linked llO to the body, a stationary guide rail disposed .x0

, ing action of the pull rod, and a ram having a thrust element to which the pull rod is coupled, said lifting arm having an irregular lever edge adapted to co-operate with the guide rail in l,causing the lifting effort of the ram equalizing at various Vperiods of lift.

14. In combination with a chassis, a dump body hinged upon said chassis. to swing upwardly, lifting bars hinged at the sides the chassis and adapted to apply a lifting force to said body at either side thereof, a ram disposed longitudinally of the chassis between said lifting bars, said ram including a cylinder and a piston therein, a pair,

of wedging elements, one for each lifting bar, an equalizing bar pivoted medially thereof on said piston, a pull-rod joining onel end of said bar with one wedge element and a second pull-rod joining the other end of said bar with the other wedging element, the joint between each link and said equalizing bar constituting dual pin and slot connections,l whereby the leverage of said equalizing bar upon said pull-rods may shift. to exert the stronger force against that pull-rod meeting the greatest resistance in the lifting of the dump body.

15. In combination with a chassis, a dump body hinged thereon to swing upwardly, a ram carrled by the chassis and including a piston rod, a cross-bar pivoted medially thereof on saidpston rod,'pullrods, one for each end of said cross-bar, means operat-ively associating said pull-rods, each with one side of the d ump body, for swinging said body upwardly, said cross-bar having four similar slots therein, two at each end thereof and all aligned longitudinally of said cross-bar, but extending in length transversely of the same, and a pair of pins in each pull-rod, one for eachslot in one end of Said cross-bar, the pins in each pull-rod being adapted both to engage the ends of their respective slots under equal pulls on said rods and adapted severally to engage the ends of their respective slots under unequal pulls on said rods, whereby the thrust of the piston rod is equalized on the two pull-rods and said piston, in turn, protected against bending strains.

16. In combination with a chassis, a dump body hinged upon said chassis to swing upwardly, a ram carried by the chassis and including a piston rod, a cross-bar member pivoted medially thereof on said piston rod, pull-members, one for each end of said crossbar member, means operatively associating said pull-members with opposite sides of said dump body for swinging said body up wardly, the connection'between each end of said cross-bar member and its respective pull-member comprising a pair of slots in one member relatively arranged longitudinally of the cross-bar and a pair of pins secured to the other member and slidably fitted. one in each of said slotsl MELVIN SWARTOUT MARTIN. 

